South-east Asia's threatened ecosystems

Business Times 1 Mar 08;

SO you thought the Borneo rainforest was the only part of South-east Asia to qualify as a threatened biodiversity hotspot? Not so. The region actually has not one but three such areas, which contain a disproportionate variety of the world's species and are critical to keeping the world's ecosystem in balance.

The richest collection of marine biodiversity, for example, is found in the Coral Triangle - a stretch of 5.7 million square kilometres of ocean, or about half the land area of the US, which spans Sulu and Sulawesi Seas surrounding Indonesia, Malaysia, and the Philippines.

The seas contain more than 600 reef-building coral species, some three-quarters of those known to man, versus just 60 in the Caribbean.

They support not only the world's largest variety of reef fish, but also commercial and community fisheries - over 150 million people live in the area, and 2.25 million of them are fishers, according to the Nature Conservancy. The reefs and beaches, where sea turtles come to make their nests, also attract tourists.

However, overfishing and destructive fishing methods, such as the use of cyanide or dynamite, have unnecessarily depleted fish populations and destroyed large sections of coral. The widespread coral bleaching means young fish lose their habitats and this will severely impact fishing stocks in the long term. It could also lead to heavy growth of algae, starving the waters of light and oxygen.

Back on the Asian continent, the Mekong River winds through deep gorges and mighty flood plains on its nearly 4,500 km journey from the Jifu mountains in Tibet down through Yunnan, Guangxi, Myanmar, Vietnam, Cambodia, Thailand and Laos.

The Mekong's waters host over 1,300 species of fish, including several of the world's largest freshwater species, and a wide variety of water plants.

Its catchment area and river delta are home to over 300 million people, with a gross product of over US$400 million per annum, according to WWF.

Wars of the past mean the region is relatively untouched by environmentally destructive forces, but large-scale economic development, extreme poverty and population pressure are now stressing the resources.

If no action is taken, the region could lose over 50 per cent of its land and water habitats over the next century, the World Bank says. This would severely impact growth, as forests help to reduce floods and erosion while the rivers enrich padi fields and provide fish and drinking water.

Meanwhile, Borneo, the world's third largest island, hosts an incredible 15,000 plant species and thousands of animal species, from the nearly extinct Sumatran tiger, to walking catfish, orang utans, rhinos, elephants, and even an unidentified cat-like mammal species dubbed the 'Bornean Red Carnivore'.